C# :Windows App single event handler

[Shani Aulakh]

Hi there,

I just started learning C# and i dont really have much experience with object oriented programming languages. I have to write a method in C# which can call all the panels. I dont know how to do this. My supervisor told me to do that. He doesn't want me to write the same code over and over again for the same purpose. I m stuck on this from a long time now. Any help will be appreciated. Thanks,
Shani

 
        private void panel1ToolStripMenuItem_Click_1(object sender, EventArgs e)
        {
            if (panel1.Visible == true)
            {
                this.panel1.Visible = false;
            }
            else
            {
                this.panel1.Visible = true;
            }
        }
 
        private void panel2ToolStripMenuItem_Click_1(object sender, EventArgs e)
        {
            if (panel2.Visible == true)
            {
                this.panel2.Visible = false;
            }
            else
            {
                this.panel2.Visible = true;
            }
        }
 
        private void panel3ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (panel3.Visible == true)
            {
                this.panel3.Visible = false;
            }
            else
            {
                this.panel3.Visible = true;
            }
        }
 
        private void panel4ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (panel4.Visible == true)
            {
                this.panel4.Visible = false;
            }
            else
            {
                this.panel4.Visible = true;
            }
        }
 
        private void panel5ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (panel5.Visible == true)
            {
                this.panel5.Visible = false;
            }
            else
            {
                this.panel5.Visible = true;
            }     
        }
 

[Plater]

So you need a single event handler that will be assigned to all of the menu items and that single event handler needs to know which panel to show/hide?

Use the "object sender" argument to determine what to do.
Maybe like:

private void MenuItem_Click(object sender, EventArgs e)
{
   if (sender ==panel1ToolStripMenuItem)
   {//change Panel1
      panel1.Visible = !Panel1.Visible;
   }
   else if (sender ==panel2ToolStripMenuItem)
   {//change Panel2
      panel2.Visible = !Panel2.Visible;
   }
   //etc etc etc
}
 

I can't really offer you much more then that. We're not supposed to do people's assignments for them.

[JosAH]

@OP: I've removed your identical post from the Java Forum; good luck.

kind regards,

Jos

[Shani Aulakh]

Hey Plater,

Thanks for your reply. I tried what you suggested.

if (sender == panel1ToolStripMenuItem)
            {//change Panel1
                panel1.Visible = !Panel1.Visible;
            }
            else if (sender == panel2ToolStripMenuItem)
            {//change Panel2
                panel2.Visible = !Panel2.Visible;
            }
            else if (sender == panel3ToolStripMenuItem)
            {//change Panel3
                panel3.Visible = !Panel3.Visible;
            }
            else if (sender == panel4ToolStripMenuItem)
            {//change Panel4
                panel4.Visible = !Panel4.Visible;
            }
            else if (sender == panel5ToolStripMenuItem)
            {//change Panel5
                panel5.Visible = !Panel5.Visible;
            }
 

It says that "The name 'Panel1' does not exist in the current context." When i run the windows form. It still works. May be it showing me the last successful built. When i had seperate evenhandler for each panel. How do i correct this?
Thanks again,

[Plater]

I thought I just copy/pasted what you had, maybe I misspelled/mis-capitalized your objects?

[Shani Aulakh]

yes, i noticed later. You mis-capitalized. I commented out the code for each seperate panel and I ran what you suggested. Now, When i try to run the program, it gives me the following error.
 
'WindowsApplication1.Form1' does not contain a definition for 'panel1ToolStripMenuItem_Click_1'
 
so does it shows the same error message for all panels. I went to the Designer form and I deleted         
 
this.panel1ToolStripMenuItem.Click += new System.EventHandler(this.panel1ToolStripMenuItem_Click_1);
 
for all panels. Now, when i run the program it gets built successfully. But when i click the menuitems panel 1, 2... it doesn't disappear the panels I dont want.
Thanks,
 

[Plater]

Go to the designer (like the visual part and not the code)
and select each menu item.
In the properties window click the lightening bolt to see the events.
In the Click event, select that same singular eventhandler for each menu item.

[Shani Aulakh]

Thank you so much!
I just followed your instructions and it worked. Your so helpful. Thanks again